Pen



FIG. 1 is a top, right front perspective view of a pen showing my new design;

FIG. 2 is a left side elevational view thereof;

FIG. 3 is a right side elevational view thereof;

FIG. 4 is a rear elevational view thereof;

FIG. 5 is a bottom plan view thereof; and,

FIG. 6 is a top plan view thereof.

FIGS. 5 and 6 have been drawn to an enlarged scale with respect to FIGS. 1 through 4. 

The ornamental design for a pen, as shown and described. 